Synthesis, structural characterization, and biological evaluation of novel antimony(III) thiosemicarbazone complexes with uncommon geometries

The synthesis, structural characterization, and biological evaluation of novel antimony(III) thiosemicarbazone complexes containing thiophene-derived ligands are reported. Two complexes were synthesized: {[SbBr2(kappa 2-N3, S-Hatetsc)]} (1) and {[SbCl2(eta 1-S-Hatmtsc)(kappa 2-N3,S-Hatmtsc)]} (2). X-ray crystallography revealed complex 1 adopts a distorted seesaw structure, while complex 2 has a distorted square pyramidal structure. Both complexes showed significant antiproliferative activity against HeLa cancer cells. They also exhibited enhanced antibacterial activity against Gram-negative bacteria, particularly Escherichia coli. This study highlights the potential of thiophene-based antimony(III) complexes as promising candidates for anticancer and antibacterial therapies.